Duct module.datalog

A Duct module that adds Integrant keys for a Datomic-like database.

Databases currently supported:

• Datalevin

Installation

Add the following dependency to your deps.edn file:

org.duct-framework/module.datalog {:mvn/version "0.1.0"}

Or to your Leiningen project file:

[org.duct-framework/module.datalog "0.1.0"]

Usage

Add a key :duct.module.datalog/<database> to your configuration, where <database> is the Datomic-like database that you're using. For example:

{:duct.module.datalog/datalevin {}}

In the :repl profile this will create a local database in the db directory and add the following convenience functions to the REPL:

• (conn) - returns the database connection
• (db) - returns a database instance
• (q query & inputs) - query with the database as the first input
• (transact tx-data) - apply a transaction to the database

In the :test profile this will create a temporary database, either in-memory if possible, or in a temporary file or directory that will be cleaned up when the system is halted.

In the :main profile the database URL is set using a var that can be set via a command-line argument or via an environment variable. The name of the var depends on the database being used.

Datalevin

Accepts an extra :schema argument:

{:duct.module.datalog/datalevin
 {:schema {:name {:db/valueType :db.type/string
                  :db/unique    :db.unique/identity}}}}

In the :main profile the Datalevin connection can be set via:

• --datalevin-dir command-line argument
• DATALEVIN_DIR environment variable

License

Copyright © 2026 James Reeves

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.